Lithographic process.



IMILTON ItUSLING WOOD, OF EAST ORANGE, NEW JERSEY.

LITHOGRAPHIC PROCESS.

No Drawing.

To all whom it may concern Ee it known that T, MILTON RUsLING YVooo, a citizen of the United States, and a resident of East Orange, in the county of Essex and State of New Jersey, have invented certain new and useful Improvements in Lithographic Processes, of which the following is a specification.

My invention relates to a process for making printing plates, and the main object thereof is to n ake a printing plate whereby the eifect of a design upon one object may be produced upon another object.

The particular result attained at present by my process is in the production in ink, on one object, of the effect of a design printed upon linoleum with oil pigments, in order to produce light and inexpensive samples of the various designs of linoleum, and avoid the necessity for carrying heavy and cumbersome sections of the linoleum.

The result may be accomplished in the usual manner by means of photography and lithography, but this is a costly method by reason of the fact that it requires the services of an artist in manually producing the designs upon plates or stones previous to etching. My process, however, is direct, entirely eliminates the services of the artist, and saves much time in reproduction and expense.

In the practice of my present invention I first pass a plate of suitable material, such as nine or aluminum, through the printing machine used for printing the designs in oil pigments upon linoleum, and print on said plate, with said oil pigments by means of the printing plate of said printing machine, the desired design, after which the freshly printed plate is removed for treatment. The printed plate is then immediately subjected to the action of a suitable etching medium, before the oil pigments have had a chance to dry or the oil thereof to spread beyond the limits of the printed dots or lines; if this etching is not immediately performed, the oil of the pigment oozes out of said pigment and spreads over the plate outwardly of the dots or lines of the design; the etching medium could not penetrate this oil and the plate would, there fore, be etched only on the clean spaces or surfaces and the design would be lost. The printed plate is then thoroughly cleansed of both pigment and etching medium, after the etching has progressed sufficiently far, and

Specification of Letters Patent.

Application filed. August 22, 1914.

Patented Apr, f3, 1915,.

Serial No. 858,091.

is ready for printing upon paper or the like with conventional ink.

The printing upon linoleum and oil-cloth is done with oil pigments, actually paint, which will withstand wear from persons walking thereover, and the dots and lines of the designs are usually in relief with respect to the surface of the linoleum; this relief is occasioned by reason of the fact that a relatively considerable quantity of paint is deposited upon the surface of the linoleum in the positions of the dots and lines, very much as though a pin were immersed in paint and the point thereof, carrying a globule of paint, then touched to the surface of the linoleum, the resultant dot being very much greater in diameter than the point of the pin, and also being in relief over said surface. The dots and lines of the linoleum printing plate are, therefore, considerably less dense than the resulting dots and lines on the linoleum printed therewith, and this printing plate, if employed with conventional ink upon paper, would not reproduce the effect of the design upon the linoleum because of its relatively small dots and thin lines. In order, therefore, to reproduce this effect it is necessary to make a printing plate wherein the dots and lines are of the density of those in the design to be reproduced, and this I do by printing on the Zinc or other plate with the same printing plate, with the same oil pigment, and in precisely the same manner, as the design is printed upon the linoleum. The plate is then immediately etched to prevent the oil from destroying the sharpness of the edges of the dots and lines of the design by spreading outwardly thereof, and this immediate etching constitutes an essential step in my process, and it will be noted that the dots and lines of the design on my plate, when finished, are much heavier than those on the linoleum printing plate and, therefore, impressions made with my plate produce the exact effect, with conventional ink, of the design of the linoleum, but not in the relief of the linoleum, because of the difference between the pigment and ink. My process, therefore, differs materially from the conventional lithography because of the necessity for immediate etching after printing on the plate, this not being necessary nor even possible in conventional lithography, and it will be also seen that a great saving in the cost of production and in time is efi'ected by dispensing with the full designs or duplications thereof.

Having fully described my invention, What I claim as new, and desire to secure by Letters Patent, is zv '1. The herein described process of producing a printing plate, consisting of impressing a design thereon with oil pigments, im-

mediately subjecting the plate to the action of an etching medium, and thoroughly cleansing the plate.

2. The herein described process of producing a printing plate, consisting of impressing a design thereon of relatively heavy density by means of a printing element having the design thereon of relatively light density, immediately subjecting the plate to the action of an etching medium, and thoroughly cleansing the plate.

'3. The herein described process of reproducing, with ink, designs printed with oil pigments, consisting of printing upon a plate with said oil pigments, immediately subjecting the printed plate to the action of a corrosive, thoroughly cleansing said plate, applying printing ink to the plate, and impressing the same upon the object to carry the reproduction.

a. The herein described process of producing, on one object, the eli'ect of a design on another object, consisting of impressing the design of a relatively heavy density upon a plate by means of a printing element having the design thereon of relatively light density, immediately subjecting the plate to the action of an etching medium, thoroughly cleansing the plate, applying ink thereto, and impressing the same upon said first named object.

In testimony whereof I have signed my name to this specification in the presence of two subscribing witnesses.

MILTON RUSLING- WOOD.

Witnesses:

JOSEPH W. ZIPFU, LOUIS J. HERTLIN.

C'opies of this patent may be obtained. for five cents each, by addressing the Commissioner of Patents, Washington, D. C. 

